i need ppt for speed and current control of bldc motor using sliding mode
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An improved sensorless operating scheme for the brushless motor control system (BLDC) is proposed. A high-speed slider mode (SMO) observer is used for the estimation of the electromotive rear force (posterior EMF) to obtain position and velocity. A speed control algorithm for BLDC control systems is developed which combines a sliding mode controller with a disturbance observer (DOB) to restrict the speed fluctuation caused by abrupt change of load torque. The DOB is used to estimate the load torque and generate a feedback compensation signal for a controller. The detailed simulation results show that the proposed high-speed SMO could improve the accuracy of the estimation and the designed compensation scheme could improve the robustness against the sudden change of the load torque.
The sliding mode control topology is used in the mechanical speed loop control as well as in the stator current loop control. The results show good vibration reduction, good machine performance and good controller robustness due to disturbances, with no need for fine tunneling of the controller parameters, as in other types of control. The parameters of an actual machine where they are used in the simulations. This type of function in the sliding mode drivers used became a very good alternative depending on the application.
HISTORY
The Variable Structure System (VSS) with sliding mode control was proposed and elaborated in the early 1950s in the Soviet Union by Emelyanov and several researchers. At the outset, VSS is well known as a special class of nonlinear systems for solving several specific control tasks in linear and nonlinear second order systems. However VSS did not receive wide acceptance among engineering professionals until 1977, the most interesting fact is that robustness has become an important requirement in modern control application. The design performance of low-order control systems, such as proportional-integral derivative (PID) controllers, is less effective for electromechanical systems such as DC units. The parametric uncertainty introduced by the mismatch of the plant model degrades the overall system performance, since these uncertainties are hardly considered in the design of linear controllers such as PID. Over the last few decades, the design of the robust control system for plant model mismatch processes has received considerable attention in the control community. Among the design approaches established for robust process control, sliding mode control (SMC) plays an important role because it can not only stabilize certain systems and uncertain but also provide the ability to reject disturbances and insensitivity to parameter variations